I think their findings are applicable to lots of languages where the fastest known implementation is JIT based. Not all “JIT dominant” languages rely on ICs as

I think their findings are applicable to lots of languages where the fastest known implementation is JIT based. Not all “JIT dominant” languages rely on ICs as part of the JIT’s performance story, but enough of them do that it’s worth studying. And JS happens to be the language where ICs have been taken the furthest, in terms of just how many different ways have been investigated and how many person years went into tuning them. So in some sense they’re picking the hardest fight. I think that’s a good thing.